Outboard gem



May 11, 1965 s..c. RETHORST OUTBOARD GEM 2 Sheets-Sheet 1 Filed May 13, 1963 FIG 4 /N VENTOR 3% scorr c. RETHORST May 11, 1965 s. c. RETHORST OUTBOARD GEM 2 Sheets-Sheet 2 Filed May 13, 1963 INVENTOR.

SCOTT 6. RETHOPST United States Patent 3,182,627 OUTBGARD GEM Scott C. Rethorst, 1661 Lombardy Road, Pasadena, Calif. Filed May 13, 1963, Ser. No. 280,764 Claims. (Cl. 115-1) This invention rel-ates to a Ground Eitect Machine (hereinafter referred to as a GEM). In particular, it re.- lates to a small craft so designed that, when equipped with an outboard motor suitably modified as specified herein (or equipped with an outboard/ inboard drive not described in this specification but employing the same concept of adaption to produce pressurized air, and modifica tion to gain independence of external water cooling) it can operate as a displacement vessel or above water and ground surfaces as an annular jet type of GEM.

It is the general object of this invention to produce :a small craft emancipated from the speed limiting penalties of water drag against the hull, and further to give such a craft an over land capability and eliminate the problems of launching and beaching a small displacement vessel.

With these and other objects in view, the invention comprises the organization of principles and the arrangement of parts herein described, and illustrated in the accompanying drawings. It is to be understood, however, that the aforementioned descriptions and drawings do not limit the scope of the invention from that expressed by the claims hereunto appended.

Of the accompanying drawings, forming part of this specification, in which like reference numerals designate like parts in the several views:

FIGURE 1 is a perspective view of the GEM, powered with an outboard motor, translating over water,

FIGURE 2 is a side View of the GEM of FIGURE 1, showing air being drawn into the intake fan, with which the outboard motor is modified, and exhausted through the peripheral tube at the underside of the GEM.

FIGURE 3 is a plan view of the GEM of FIGURE 1 showing the hinged rear section that houses the modified outboard motor, and the segmented peripheral tube from which the annular jet is emitted.

FIGURE 4 is a cross section of the GEM hull of FIG- URE 3 showing the housing of the peripheral tube.

FIGURE 5 is a perspective view of the peripheral tube and housing of FIGURE 4,

FIGURE 6 is a schematic representation of the fan, the radiator, the peripheral tube, and the air flow associated with them,

FIGURE 7 is an expanded elevation of the modified outboard motor of FIGURE 2,

FIGURE 8 is a side view of the aft portion of the GEM of FIGURE 2 during hovering above land or water, or translation above a land surface.

Referring now to the drawings and describing this invention in detail, the GEM of FIGURE 1 is equipped with a rear section 21 hinged at point 22 (and also at point 23 in a corresponding position on the right side of the GEM 29, but not shown in this View) so that the rear section 21 may be pivoted from its horizontal position for a purpose to be explained. The rear sect-ion 21 houses a conventional outboard motor 24 modified in a manner to be described. The outboard motor 24 provides the total power of the GEM 20 for its several modes of operation: as a displacement vessel; as a GEM translating above Water, using a water propeller; or as a GEM translating above land or Water, using air propulsion. In FIGURE 1 the GEM 20 is shown translating above a water surface 25.

The GEM 20, in all its modes of opera-tion other than as a displacement vessel, is supported on a cushion of air developed by the air jet emitted from the peripheral tube 3,182,627 Patented May II, 1965 26 shown in the side view of FIGURE 2. The outboard motor 24, modified with a fan in a manner to be described, causes air to be drawn into the intake 27 and emitted from the peripheral tube 26.

The peripheral tube 26, shown in the plan view of FIG- URE 3, is segmented at points 23 through 37 in order that individual linear segments so formed may be rotated independently of each other for a purpose to be explained. The segmentation of the peripheral tube 26 produces four corner segments 26a, 26b, 26c, and 26d. These latter segments do not rotate, but enclosure of an inch or so of each adjoining segment of the peripheral tube 26, much in the manner of a telescope, permits the free rotation of the individual segments without interruption of the passage of air.

The segmented peripheral tube 26 around the periphery of the GEM 20, located at the underside thereof, is contained Within the circular housing 38 shown in the cross section of FIGURE 4. With their movement governed by the control 39a, individual segments of the peripheral tube 26 are free to rotate within the circular housing 38. Pressurized air is emitted from the slot 39b extending the entire length of the peripheral tube 26. The wider slot 4?), extending the length of the circular housing 38, permits the air jet emitted from the peripheral tube 26 to be deflected at variable angles governed by the control 39a, thereby providing directional control of the GEM 20. For example, the segments of the peripheral tube 26 between points 31 and 32, and 28 and 37, shown in FIG- URE 3, may be partially rotated left or right by using the control 39a of FIGURE 4 to cause a corresponding left or right turning of the GEM 20.

Braking or additional thrust of the GEM 29 is obtained by using the control 3% of FIGURE 4 to rotate the segments of the peripheral tube 26 between points 34 and 35, and 29 and 30, shown in FIGURE 3, and causing a forward or rearward deflection of the air emitted from those 7 segments and a corresponding braking or thrusting force to the GEM 20.

For operatioin of the GEM 2d as a displacement vessel, the slots 39b of the peripheral tube 26, and the slot 40 of the circular housing 38, are sealed from each other by full movement of the control 39a. Thus, during the displacement role of the GEM 26), water is unable to enter the peripheral tube 26. The perspective view of FIGURE 5 illustrates this full movement of the peripheral tube 26- within the circular housing 38.

The schematic of FIGURE 6 shows the flow of air from the intake 27 to the air chamber 41. From the air chamber 41, the air passes through a radiator 42 whose purpose will be explained Beyond the radiator 42 the air is ducted through ducts 43] (left) and 43r (right) and through the flexible ducts 44! (left) and 4-41 (right) into the peripheral tube 26 where it is exhausted in the man ner already described.

The outboard motor 24, modified to produce the necessary flow of air through the system described, is shown in FIGURE 7. The motor 24 is modified with the addition of a squirrel cage type fan 45 and an air inlet 27. Toaccommodate these modifications, the shaft 46 of the motor 24 has been lengthened. The fan 45 does not revolve when the clutch 47 is disengaged from the shaft 46.

Further modifications to the outboard motor 24 are the additions of the water tank 48, the radiator 42, the water pipes 49, 5t and 51, and petcocks 521'and 53 at the inlet and outlet respectively of the normal, unmodified water Cooling system. The modifications accomplish cooling of the outboard motor when, for reasons to be explained, the outboard motor 24 is unable to draw in cooling water from an external source.

The water pipe 51 is connected to the inlet of the normal cooling system of the outboard motor 24 and the water pipe 50 is connected to the outlet. When the petcocks 52 and 53 are closed, circulation of water from the tank 48 is maintained throughout the normal cooling circuit of the motor 24 by the water pump 54.

When the GEM is operating above a land surface, the rear section 21 is raised to the position illustrated by FIGURE 8 and the outboard motor 24 is still running to drive the fan 45 and supply air to the peripheral tube 26. The water propeller 55, however, is declutched from the motor 24 by the mechanical or magnetic clutch normal for outboard motors. The water pump 54 pumps hot water from the normal cooling circuit of the outboard motor 24 and forces it through the water pipe 50, thence through the radiator 42 where it is cooled by the flow of air from the fan 45, and then through the water pipe 49 and into the water tank 48. The flow of cooling water is completed by the water pump 54 drawing cold water through the pipe 51 from the tank 48.

When the GEM 20 is operating as a displacement vessel, a choice of cooling systems is available. The valves 57 and 58 in the air ducts 431' and 431 may be opened so that the air from the fan 45 (no longer necessary for the support of the craft in this role) is exhausted at those points. Before reaching the valves 57 and 58, however, the air has passed through the radiator 42 and cooled the water therein. Thus, the modified cooling system of the outboard motor 24 may be used during operation of the GEM 20 as a displacement vessel. The second choice is the use of the normal, or unmodified cooling system of the outboard motor 24. To employ this system, the fan 45 is declutched from the shaft 46 by the clutch 47 and the petcocks 52 and 53 are opened. The water pump 54 draws cold water into the cooling circuit of the motor 24, through the petcock 52, pumps it around the cooling circuit and ejects it through the petcock 53.

When the GEM 26 is translating over land, the rear section 21 is raised so that the propeller 55 is clear of the surface 56, as shown in FIGURE 8. The propeller 55 is declutched from the motor 24 by the magnetic or mechanical clutch normal for outboard motors (not described or illustrated in this specification, owing to the diversity of such devices). The motor 24 is running, cooled by its internal or modified cooling system previously described, and driving the fan 45. The valves 57 and 58 are closed and the peripheral tube 26 emits the air necessary to cushion the GEM 20 above the ground. The segments of the peripheral tube between points 29 and 3t), and 34 and 35, shown in FIGURE 3 are partially rotated so that the rearward deflection of the air emitted from the peripheral tube 26 gives forward thrust to the GEM 20.

A brief description of the outboard GEM in its different modes of operation follows:

(1) As a displacement vessel.The rear section is in the normal or horizontal position so that the propeller is immersed in the water. The peripheral tube is sealed from the Water by rotation of the tube within its housing so that the slot which normally emits the annular jet is no longer aligned with the slot of the tube housing. The choice of cooling systems is available to the operator, and the craft is able to operate as an ordinary, flat-bottomed boat propelled and steered by an outboard motor.

(2) As a GEM translating above water.The fan is engaged with the drive shaft of the outboard motor, and the slot of the peripheral jet tube is aligned with the slot of the tube housing. The dump valves 57 and 58 are closed so that pressurized air is emitted from the slot of the peripheral tube and the GEM is supported on a cushion of air. The mechanical or magnetic clutch of the propeller is engaged and the GEM is driven and steered by the water propeller. Over water not deep enough to permit immersion of the propeller, or for beaching or launching operations, the rear section is raised and the GEM obtains its thrust from the rearward deflection of the air jet emitted from the front and rear segments of the peripheral tube. During this mode, a choice of cooling systems is again available to the operator, once the propeller has been immersed in water.

(3) As a GEM translating above land.The propeller is disengaged and the rear section raised from the horizontal position. The fan is engaged to the drive shaft of the outboard motor, pressurized air is emitted from the peripheral tube to provide the necessary air cushion, and the front and rear segments of the peripheral tube are partially rotated to deflect the air jet rearward for forward thrust of the GEM. Braking is accomplished by partially rotating the same segments of the peripheral tube to provide the necessary rearward thrust of the GEM. During this mode, the motor is cooled by the modified, or internal cooling system.

(4) Hovering above land or water.With the rear section raised, the fan engaged and the propeller disengaged, the outboard motor is running to pressurize the air emitted from the peripheral tube for the necessary air cushion. With the petcocks of the inlet and outlet closed, the outboard motor operates on its modified, or internal cooling system.

Having thus described my invention, what I claim as novel and desire to secure by Letters Patent of the United States is:

1. An amphibious GEM, comprising:

a boat hull;

sectionalized downwardly directed nozzle means disposed peripherally around the boat hull to provide an air cushion between the hull and a water or land surface underneath said hull as well as thrust for translation;

means for sectionally closing said nozzle means;

a motive power source;

a fan connected to said power source for delivering pressurized air to said nozzle means to lift said hull completely from the water or land surface;

a water propeller pivotally mounted for operation under Water and for retraction from the water to a position above the surface;

and means for selectively connecting and disconnecting said propeller and said power source permitting said power source to drive said fan independently from the position of said propeller.

2. An amphibious GEM, comprising:

a boat hull;

sectionalized downwardly directed nozzle means disposed peripherally around the boat hull to provide an air cushion between the hull and a water or land surface, underneath said hull as well as thrust for translation;

means for sectionally closing said nozzle means;

a motive power source;

a pivotable shaft driven by said motive source;

a fan connected to said shaft for providing a flow of air;

an air distribution system for delivering said air flow as provided by said fan to said nozzle means for discharge through said nozzle means to lift said hull completely from the water or land surface;

and a water propeller selectively connectable to said shaft so that said motive power source may drive said propeller, said propeller may be submerged or retracted from the water upon pivoting of said shaft.

3. An amphibious GEM, comprising:

a boat hull;

nozzle means mounted peripherally around the boat hull to provide an air cushion beween the hull and a water or land surface underneath said hull;

a motive power source;

a fan selectively connectable to said power source for providing a flow of air to said nozzle means to lift said hull completely from the water or land surface;

and a pivotable water propeller selectively connectable to said power source, said propeller and said fan being individually and jointly connectable to said power source.

4. An amphibious GEM, comprising:

a boat hull;

downwardly directed nozzle means disposed peripherally around the boat hull to provide an air cushion between the hull and a water or land surface underneath said hull;

means for selectively blocking the discharge of air from said nozzle means; and

a motive power source;

a fan for selective connection to and disconnection from said motive power source for selectively delivering pressurized air to said nozzle means to lift said hull completely from the Water or land surface;

a water propeller pivotally mounted for operation under water as well as for retraction above the surface, and being drivingly connected to said motive power source.

5. An amphibious GEM, comprising:

a boat hull;

nozzle means disposed under the boat hull to provide an air cushion between the hull and a water or land surface;

a motive power source;

a fan connected to said power source for delivering pressurized air to said nozzle means;

a water propeller pivotally mounted for operation under water as well as for retraction above the surface; and

a water cooling system for cooling said motive source and being coupled for heat exchange with the air flow from said fan to said nozzle.

6. A GEM, comprising:

a boat hull;

nozzle means being downwardly directed and peripherally disposed under said hull for providing an air cushion between said hull and a water or land surface underneath said hull;

means for selectively blocking the discharge of air from said nozzle means;

means for providing said nozzle means for selectively blocking the discharge of air therefrom;

a retractable water propeller at said GEM;

a fan for delivering air to said nozzle means to lift said hull completely from the water or land surface;

and a motor couplable to both, said fan and said propeller, and being coupled to at least one of said fan and said propeller for driving said GEM.

7. An amphibious GEM, comprising:

a boat hull;

nozzle means peripherally positioned and downwardly directed towards underneath the boat hull to provide an air cushion between the hull and a water or land surface;

a motor with shaft pivotally mounted at the rear of said hull;

a fan coupled to said shaft for delivering pressurized air to said nozzles for discharge therefrom to lift said hull completely from the water or land surface;

and a water propeller coupled to said shaft pivoting therewith for selective submerging under water and retracting from the Water surface.

8. A GEM, comprising:

a hull;

nozzle means peripherally disposed at said hull, for

directing an air flow underneath said hull;

a motor in said GEM;

a fan drivingly coupled to said motor to provide a flow of air;

an air distributing system for providing said flow of air to said nozzle means;

a heat exchanger in said air distributing system; and

a fiuid cooling system for said motor including means for passing cooling fluid through said heat exchange.

9. A GEM, comprising:

a boat hull;

a tubular housing extending around the periphery and the underside of the hull and having downwardly directed openings;

tubular segments disposed in said housing, said segments having nozzles alignable with said openings, for directing an air flow towards the surface under said hull to lift said hull completely from the water or land surface;

means for pivoting said segments for changing the direction of said air flow and for selectively misaligning said nozzles and said openings;

and power means for delivering pressurized air to said nozzle means.

10. A GEM, comprising:

a boat hull;

a tubular housing extending around the periphery and at the underside of the hull and having downwardly directed openings;

tubular segments disposed in said housing,

said segments having nozzles alignable with said openings, for directing an air flow towards the surface under said hull;

means for pivoting said segments for changing the direction of said air flow and for selectively misaligning said nozzle and said openings;

a fan for delivering air to said segments and said nozzles to lift said hull completely from the water or land surface;

a motor for driving said fan;

and a water propeller drivingly connected to said motor and being selectively retractable from the water.

References Cited by the Examiner UNITED STATES PATENTS 1,003,364 9/11 Langston 11467 1,819,216 8/31 Warner 7 3,077,321 2/63 Dunham 180-7 MILTON BUCHLER, Primary Examiner. ANDREW H. FARRELL, Examiner, 

1. AN AMPHIBIOUS GEM, COMPRISING: BOAT HULL; SECTIONALLY DOWNWARDLY DIRECTED NOZZLE MEANS DISPOSED PERIPHERALLY AROUND THE BOAT HULL TO PROVIDE AN AIR CUSHION BETWEEN THE HULL AND A WATER OR LAND SURFACE UNDER NEATH SAID HULL AS WELL AS THRUST FOR TRANSLATION; MEANS FOR SECTIONALLY CLOSING SAID NOZZLE MEANS; A MOTIVE POWER SOURCE; A FAN CONNECTED TO SAID POWER SOURCE FOR DELIVERING PRESSUREIZED AIR TO SAID NOZZLE MEANS TO LIFT SAID HULL COMPLETELY FROM THE WATER OR LAND SURFACE; A WATER PROPELLER PIVOTALLY MOUNTED FOR OPERATION UNDER WATER AND FOR RETRACTION FROM THE WATER TO A POSITION ABOVE THE SURFACE; AND MEANS FOR SELECTIVELY CONNECTING AND DISCONNECTING SAID PROPELLER AND SAID POWER SOURCE PERMITTING SAID POWER SOURCE TO DRIVE SAID FAN INDEPENDENTLY FROM THE POSITION OF SAID PROPELLER. 